Chalcogenide sputtering target and method of making the same
In one embodiment, a physical vapor deposition device includes a phase change material sputtering target includes a primary matrix and at least one additional phase. The primary matrix includes at least one element from Group VI of the periodic table excluding oxygen and one or more elements from Group IV or Group V of the periodic table. The additional phase is substantially homogenously dispersed in the primary matrix.
1. A physical vapor deposition device comprising a phase change material sputtering target, the phase change material sputtering target comprising:
primary matrix including at least one element from Group VI of the periodic table excluding oxygen and one or more elements from Group IV or Group V of the periodic table; and
at least one additional phase substantially homogenously dispersed in the primary matrix, wherein the sputtering target has a density of at least 95% of theoretical density, wherein:
the primary matrix includes arsenic and selenium and the at least one additional phase includes a germanium and selenium phase and a silicon phase;
the primary matrix includes arsenic, tellurium and germanium and the at least one additional phase includes a silicon phase; or
the primary matrix includes arsenic and selenium and the at least one additional phase includes a germanium and tellurium phase.
2. The physical vapor deposition device of claim 1 wherein the primary matrix exhibits a glass transition behavior.
3. The physical vapor deposition device of claim 1 wherein the phase change material sputtering target is free of voids between the primary matrix and the additional phase.
4. The physical vapor deposition device of claim 1 wherein each additional phase is a compound or an elemental material.
5. The physical vapor deposition device of claim 1 wherein the additional phase has a mean size of less than about 200 μm.
6. The physical vapor deposition device of claim 1 , wherein the sputtering target is substantially free of pores.
7. The physical vapor deposition device of claim 1 wherein the sputtering target has a purity of at least 99.99%.
8. The physical vapor deposition device of claim 1 wherein the sputtering target has an oxygen content of less than 1000 ppm.
9. The physical vapor deposition device of claim 1 and further comprising a backing plate connected to a back surface of the sputtering target.
10. The physical vapor deposition device of claim 1 wherein the sputtering target has less than 1% variation in atomic elemental composition across a sputtering surface.
11. The physical vapor deposition device of claim 1 wherein the primary matrix includes arsenic and selenium and the at least one additional phase includes a germanium and selenium phase and a silicon phase.
12. The physical vapor deposition device of claim 1 wherein the primary matrix includes arsenic, tellurium and germanium and the at least one additional phase includes a silicon phase.
13. The physical vapor deposition device of claim 1 wherein the primary matrix includes arsenic and selenium and the at least one additional phase includes a germanium and tellurium phase.